package java1227;

//public class D extends E {
//    public static void main(String[] args) {}
//}
//
//class E {
//
//}

public abstract class D{
    abstract int m1(int a,int b);
    abstract int m2(int a,int b);
    abstract int m3(int a,int b);
    abstract int m4(int a,int b);
}

class E extends D{
    public static void main(String[] args) {
        E e = new E();
        D d =e;
        E e2=(E)d;
    }
    @Override
    int m1(int a, int b) {
        return 0;
    }

    @Override
    int m2(int a, int b) {
        return 0;
    }

    @Override
    int m3(int a, int b) {
        return 0;
    }

    @Override
    int m4(int a, int b) {
        return 0;
    }
}
